When you look at a fund's Morningstar style box, you immediately get some insight into the manager's investment strategy. A growth portfolio will mostly contain higher-priced companies that the manager believes have the potential to increase earnings faster than the rest of the market. A value orientation, on the other hand, means the manager buys stocks that are cheap, but that could eventually see their worth recognized by the market. A blend fund will mix the two philosophies: The portfolio may contain growth stocks and value stocks, or it may contain stocks that exhibit both characteristics.
Because the style box shows you how a fund actually invests, you can use it to get an idea of what sort of risks the fund harbors today. A fund that owns smaller, more expensive stocks is bound to be more volatile than one holding large, cheap names. And the style box allows you to quickly see where a fund's portfolio lands.